DESC:FIELD OF THE INVENTION
The present invention concerns the development of novel method of formulating a free flowing premix powder containing melamine: formaldehyde (MF for brevity) fragrance capsules, and, having these delivered onto fabrics when incorporated through rinse off formats like detergent powders and laundry liquids. Particularly the present invention relates to MF capsules containing fragrance that exhibit good transfer efficiencies on fabrics even when rinse off formats such as detergent powder or laundry liquids are used in the washing process. The effective transfer and lodging of MF microcapsules onto fabrics in a rinse off situation has been accomplished using rational principles of formulation design. The first step is the formulation of a flowable MF capsule containing powder, which, is then incorporated into a detergent powder formulation. A treated and modified aqueous MF capsule slurry is added to a laundry liquid favouring having capsules well dispersed in the medium, such that, these are effectively transferred to fabric post-wash. The deposition of MF capsules using flowable premixes or aqueous slurries of MF fragrance capsules in rinse off washing formats is impacted, primarily, due to stabilization of micron sized capsules in these formats, and, importantly due to the extremely poor transfer efficiency of these capsules onto the fabrics. Advantageously, the present invention by way of employing improved system/ formulation and method of preparation of the same could attain stable MF capsules that are adequately well protected using various flowable powder mixes, (three types of mixes which are capable of this delivery) that get delivered onto fabrics even when rinse off product formats like detergent powders or laundry liquids are employed.

BACKGROUND ART
Fragrance is a consumer preferred attribute in a variety of fast moving consumer goods, and, therefore a key driver of the purchase intent. Fragrance cues and olfactory sensorials of the product category in question have a huge influence on the purchase intent of the consumer. The individual likeability of the fragrance profile, as well as, its intensity influences the overall purchase decision of the consumer, for instance, in the choice of personal application leave on products like creams and lotions. However, for product categories like personal wash bars, detergent powders and liquids for fabric wash the overall attributes which signify the likeability of the fragrance is based on olfactory assessments during various stages of the product consumption and usage cycle. Thus for example in the case of a personal wash bar, the fragrance at the point of purchase, whilst bathing, fragrance of the bloom emanating in the bathroom, as well as, retentivity of fragrance lingering on the skin post bath are assessed by the consumer to provide an objective judgement on their likeability. In slight contrast, in a laundry wash process involving detergent powders the olfactory experience during point of purchase, upon dissolution in water, upon soaking, rinsing and wringing of damp clothes, as well as, neat fragrances which tend to linger on the fabric or are delivered through the deposition of certain hard shell capsular systems containing encapsulated fragrance are important determinants of likeability with regards a specific fragrance. Examples of extended delivery of fragrances on fabrics when washed using a powder or liquid detergent are extremely rare in the art. This is because of the fact that free fragrance micellisation is extensively favoured in such formats employing surfactants. Such micelles which entrap and solubilise fragrances get washed away in laundry liquor. Approximately 3-4% of free fragrances which survive micellisation gets deposited into fabric after the wash; however, given their extremely low concentrations and deposition efficiencies do not contribute to any perceptible olfactive experience when the cloth is dried and folded.

WO 2016134994 mentions about stable dispersions containing encapsulated fragrances and fragrance oils but does not disclose a specific system. EP 2860237A1 states the coating of fragrance with a terpolymer which in turn is further coated by a cationic polymer, while, DE 102009029292A1 refers to a solid fragrance imparting composition with the free fragrance dye and beta-Cyclodextrin incorporated into PEG 8000 matrix, and, added along with MF capsule coated with a cationic polymer. US 2005 0226900A1 and US 2007 70078071A1 refer to fragrance encapsulation with the former stating that the coating on MF capsule comprises a mix of acrylamide and polyacrylic acid. The uses of porous inorganic compounds like silica and zeolites have been described in few patents to function as a carrier material. For instance, WO2011 1207687A1 talks about a dry flowable powder prepared by the addition of silica or an aluminosilicate mineral to the aqueous premix MF slurry. The use of water soluble materials used to coat the MF capsules is described in US 7125835B2, while, EP 2496676A1 hints on the use of a polysaccharide as a possible coating matrix for MF capsules and functions as a deposition aid. WO 201713480 mentions about coating the MF capsules with a sugar and silica and the use of trehalose based emulsion. WO 2015065809 indicates the benefit of using poly propylene glycol for stabilizing cationic based polymers.
Reference drawn to the above prior arts, as discussed above, while indicate the use of silica, zeolite, polysaccharide none could achieve such extended benefits of fragrance retention on fabrics through wash off formats like detergent powder or a laundry liquid wash.
While MF (melamine formaldehyde) capsules have been known in the art to be effectively delivered via the fabric conditioner product format there are noclear demonstrable examples of effective deposition of such MF hard shell capsules through a powder detergent or liquid. Such MF capsules entrapping fragrances have extremely poor transfer rates during the wash cycle in case of powder detergents and laundry liquids. Hence, their efficiency of deposition onto fabric surfaces is very poor, and, as a consequence, difficult to offer an extended fragrance experience to the consumer employing these formats.
Some prior work on direct spray drying of aqueous MF fragrance containing capsules onto detergent powders has shown that the dried capsules suffer from long term stability issues. It is well known in the art that MF capsules are stable when present as aqueous slurries and, exhibit instabilities when dried to convert them to their powder form. This is because transportation and random movements during long term storage ensure collision amongst various particles, as a consequence of which there are extensive capsule leakages. Moreover, due to the non-homogeneous nature of slurry addition the capsule deposition is non-uniform resulting in sub-optimal and non-consistent post dry fragrance experience. In any case the rates of transfer from aq MF slurries onto fabrics when rinse-off formats are employed are low, while, being compounded by stability and leakage issues.
Furthermore, the deposition of MF fragrance containing capsules is poor when delivered through liquid detergent formulations. In laundry liquids the capsules do not get homogeneously dispersed and also tend to sediment thereby leading to poor capsule deposition, and, as a consequence, poor fragrance delivery. The uniform suspension of MF capsules poses issues thereby necessitating agitation of the container prior to dosing the liquid containing capsules to the wash load.
As evident from the art described above there is a long felt need to provide extended benefits of fragrance retention on fabrics through wash off formats like detergent powder or a laundry liquid wash. While, these benefits have been adequately demonstrated and even commercially implemented in the case of fabric conditioners, extending similar benefits through rinse off formats poses issues. It is therefore the intent of the present invention to demonstrate and teach methods and processes by which such MF hard shell containing fragrance capsules can be deposited in rinse off formats, thereby, providing the consumer an extended fragrance experience even while employing detergent powders and laundry liquids.

OBJECTS OF THE INVENTION
It is thus the primary object of the present invention to provide for the development of a flowable MF capsule premix formulations involving melamine formaldehyde hard shell core fragrant capsules that would effectively deliver fragrance onto fabrics using rinse off formats. For instance, the effective delivery of MF fragrance containing capsules onto fabrics when incorporated either in a detergent powder or a laundry liquid format is at the heart of the invention.
It is yet another object of the present invention to provide for the said formulations facilitating deposition of fragrance containing MF capsules incorporated in detergent powder or liquid detergent formulations that would survive the wash off process, and, retain its ability to get lodged onto fabric surfaces, subsequent to the drying.
It is still another object of the present invention to provide for said formulations involving capsules that would get deposited on fabric surfaces and survive the rinse off process being employed wherein the delivery of MF fragrance containing capsules onto fabrics while is reported within fabric conditioner in the prior art, however, the deposition of the MF hard shell capsules containing fragrance has not been unequivocally demonstrated on fabrics, hitherto.
It is yet another object of the present invention to provide for the development of such formulation systems involving MF capsules, and, a process for the preparation of the same that would provide for enhanced deposition efficiencies of capsules through both, a detergent powder as well as a liquid detergent formulation where the capsules are well dispersed in liquid detergent and would not settle down with time.

SUMMARY OF THE INVENTION

According to the basic aspect of the present invention there is provided a slurry formulation of fragrance capsules comprising a synergistic combination of
i. hard shell capsules comprising MF(melamine-formaldehyde) capsules;
ii. silica;
iii. sugar; with moisture content in the range of 8-25% adapted as an improved vehicle for capsule integrity during storage and transportation.

Preferably said slurry formulation comprises humectants and/or cationic polymer adapted for aqueous slurry favouring premix powder with moisture content in said 8-25% range suitable for powder detergent formulations.

According to a preferred aspect of the present invention there is provided a slurry formulation of fragrance capsules comprising
i. MF (melamine-formaldehyde) capsules in the range of 5-50 wt.%;
ii. silica 0.05-85 wt.% preferably hydrophilic precipitated silica;
iii. sugar 7-95 wt.% preferably sucrose; and such that the ratio of sugar and silica is in ratio between the 65/35 to 95/5
iv. humectant 0.05-60 wt.%;
said moisture content being in the range of 10-14%.

Preferably said slurry formulation of fragrance capsules comprises
i. MF (melamine-formaldehyde) capsules in the range of 5-50 wt.%;
ii. silica 0.05-85 wt.% preferably hydrophilic precipitated silica;
iii. sugar 7-95 wt.% preferably sucrose; and such that the ratio of sugar and silica is in ratio between the 65/35 to 95/5
iv. cationic polymer 0.5-25 wt.%;
said moisture content being in the range of 10-14%.

According to a preferred aspect of the present invention there is provided a slurry formulation wherein said humectant includes silicone wax, sorbitol, Glycerol, glycols including Propylene glycol, PPG-20 Methyl Glucose Ether, Bis-PEG-18 Methyl Ether Dimethyl Silane.

Preferably is said slurry formulation said cationic polymer includes Polyquats, cationic acrylates, cationic acrylamides.

More preferably, said slurry formulation comprises hard shell capsules including MF (melamine-formaldehyde) capsules, Aminoplast encapsulates, Urea- Formaldehyde Capsules

According to another preferred aspect of the present invention there is provided said slurry formulation comprising fixatives including glycerol, silicones, esters, acrylates; and additives including sodium chloride, sodium Carbonate, calcium carbonate, calcium magnesium carbonate, hydrated magnesium silicate.

According to another aspect of the present invention a method of preparation of slurry formulation of fragrance capsules is provided comprising simple blending of a synergistic combination of ingredients comprising
i. hard shell capsules comprising MF (melamine-formaldehyde) capsules;
ii. silica;
iii. sugar;
in hierarchical manner and controlling the moisture content in the range of 8-25% and obtaining therefrom said slurry formulation adapted as an improved vehicle for capsule integrity during storage and transportation.

Preferably said method of preparation of slurry formulation comprises blending said silica-sugar combination in two distinct phases with said hard shell capsules comprising adding about 85% of silica-sugar in the first step and remaining 15% post mixing in the first step with moisture controlled in the levels of 10-14 % favouring optimal post dry fragrance deposition.

According to another aspect of the present invention there is provided a slurry formulation of fragrance capsules suitable for liquid detergents comprising positively charged cationic polymer 0.5-10wt.% preferably in the range of 1-5 wt.% as a synergistically co-acting suspension aid suspension aid in a surfactant medium favouring not only stable dispersion of hard shell capsules in said liquid detergent formulations but also enhanced fragrance performance/ strength and profile on fabrics post dry.
Such synergy could not be attained for other capsules not in accordance with the present invention and no fragrance performance /strength an profile could be attained.

BRIEF DESCRIPTION OF FIGURES

Figure 1a-d: illustrates the strength profile of the various types of fragrances in various formulations and comparisons thereof;
Figure 2a-b: illustrates the profile and the strength of the formulation in accordance with the present invention vis-à-vis the comparatives conventionally known and control formulations;
Figures 3a-b: illustrates profile and strength of Formulation 3;
Figures 4a-b: illustrates profile and strength of Formulation 4;
Figures 5a-b: illustrates profile and strength of liquid detergent based on the cationic polymer therein;
Figures 6a-b: illustrates microcap dilution study;
Figure 7: illustrates optical Images of Premixes of MF Slurries aged 1 month added to Detergent Powders.

DEATILED DESCRIPTION OF THE INVENTION

As discussed hereinbefore, the present invention relates to formulations/systems which enable the successful deposition of MF (melamine-formaldehyde) hard shell capsules containing fragrances onto fabrics post-washing and drying though rinse off formats. The present invention particularly concerns the effective stabilization and delivery of the capsules onto fabric surfaces even when rinse off formats is employed for the purposes of fabric cleaning and care.
The system of the present invention when combined with aqueous MF premix slurries serves as aim proved vehicle for protecting the capsule integrity during the wash process and ensuring effective transfer and deposition of MF capsules onto fabric surfaces.
According to an embodiment of the present invention there is provided MF capsules comprising select ingredients of silica, sugar, certain fixatives, as a premix, when added to an aqueous slurry, to result in a powder, ensures capsule integrity that is well protected without any stability issues resulting from transportation and storage. Also as a consequence of this modification to the aqueous MF slurry there are minimal capsule leakages resulting in minor fragrance losses during its storage and transport.
Moreover, another aspect of the present invention is the method of addition of said select ingredients involving a certain hierarchy of addition of ingredients which when followed results in stable pre-mixes with uniform deposition resulting in optimal post dry fragrance experience, and if added in a random manner, results in unstable pre-mixes wherein the capsule deposition becomes non-uniform. The method of the present invention therefore circumvents the prior art hurdle, wherein, the capsules suffered from stability issues due to transportation and storage leading to capsule leakages. Such a situation is encountered upon direct addition of aqueous slurries of MF to detergent powders or spray drying MF capsules onto detergent powders. Moreover, due to the non-homogeneous nature of slurry addition the capsule deposition used to be non-uniform resulting in sub optimal post dry fragrance experience.
Thus the pre-mix preparation in accordance with the invention thus needs to follow a certain hierarchy of addition of reagents, which when altered does not result in stable premixes. So, the manner of preparation of the pre-mixes are important.
Thus according to an aspect of the present invention there is provided MF capsule formulation (1st formulation) as slurry formulation favoruing a pre-mix comprising ingredients MF capsules, silica, sugar, certain fixatives, in certain wt% ranges adapted for an aqueous slurry convertible into powder formulation;
Preferably the moisture level of said premix formulation controlled in the levels of within 8-25% range, most preferably 10-20% range is also surprisingly found to be an important factor for ensuring stability of the MF capsules.
The Premix formulations of the present invention viz., Systems A, B and C as described in the Table 1 below were free flowing in nature, yet, had a total moisture content preferably in the range of 10-14%, which ‘free flow’ property of the premix is an important factor allowing homogeneous mixing and distribution within detergent powder.

In accordance with the invention at least three formulations which differ in their compositions are disclosed that includes the MF capsules. The effective delivery of MF capsules through detergent powders has been achieved through a conversion of the original aqueous MF formed slurry to a dry flowable powder. It was found to be meaningful to work with standard MF slurries having a defined solid content. The MF capsules within this dry powder are well protected and thereby maintain their integrity with time. The moisture level in the final premix flowable powder is within 10-20% range, and, is surprisingly found to be an important factor for ensuring stability.

Examples: MF capsule delivery on fabrics through Detergent Powders
Preferred ingredients in their respective wt% range are taken leading to the preparation of three such premix formulations (MF slurry + actives which form a free flowable powder having a moisture content of approx 8-14%). The resulting pre-mix is added to the detergent powder following which fragrance evaluation is conducted on the fabric post-laundry wash. The panel based olfactory evaluation data proves that the effective deposition of MF capsules incorporating fragrance has been attained. In control experiments where only fragrance is used the effect of fragrance deposition and lingering is not observed at all. In fact, most of the fragrance load gets partitioned or solubilized in surfactant micelles get away in the laundry wash liquor.

Table 1:Set A Formulation

S. No Ingredients Original Formula Formulation 1 Formulation 2 Formulation 3 Formulation C
1 Microcap
(Fragrance 5% - 50%) 18.5 05.00 - 40.00 07.00 - 45.00 10.00 - 50.00 20.00
2 PPG-20 Methyl Glucose Ether 5.00 0.05- 60.00 0.005 - 50.00 0.01 - 40.00 5.00

3 Sucrose 65 10.00 - 95.00 15.00 - 80.00 07.00 - 70.00 64.00
4 Sodium Chloride 0.05 0.10 - 10.00 0.20 - 15.00 0.03 - 20.00 0.05
5 Precipitated Silica 11.4 0.05 - 70.00 0.10 - 80.00 01.00 - 85.00 7.00
6 Colour Paste 0.05
Total 100

Moisture content of Premix = 13.25 %

Table 2: Set B Formulation

S. No Ingredients Original Formula Formulation 1 Formulation 2 Formulation 3 Formulation C
1 Microcap
(Fragrance 20% - 50%) 20.00 05.00 - 40.00 07.00 - 45.00 10.00 - 50.00 20.00
2 Bis-PEG-18 Methyl Ether Dimethyl Silane 1.00 0.05- 60.00 0.005 - 50.00 0.01 - 40.00 1.00

3 Sucrose 67.5 10.00 - 95.00 15.00 - 80.00 07.00 - 70.00 63.00
4 Sodium Chloride 0.05 0.10 - 10.00 0.20 - 15.00 0.03 - 20.00 0.05
5 Precipitated Silica 11.4 0.05 - 70.00 0.10 - 80.00 01.00 - 85.00 9.00
6 Colour Paste 0.05
Total 100

Moisture content of Premix = 14.00 %

Table 3: Set C Formulation

S. No Ingredients Original Formula Formulation 1 Formulation 2 Formulation 3 Formulation C
1 Microcap
(Fragrance 20% - 50%) 19.5 05.00 - 40.00 07.00 - 45.00 10.00 - 50.00 20.00
2 acrylamido-N-propyltrimethylammonium chloride/ 4.00 0.50- 15.00 0.50 - 20.00 01.00 - 25.00 4.00
acrylamide
3 Sucrose 65.00 10.00 - 95.00 15.00 - 80.00 07.00 - 70.00 62.00
4 Sodium Chloride 0.05 0.10 - 10.00 0.20 - 15.00 0.03 - 20.00 0.05
5 Precipitated Silica 11.4 0.05 - 70.00 0.10 - 80.00 01.00 - 85.00 8.00
6 Colour Paste 0.05
Total 100

Moisture content of Premix = 12.55 %

Under all comparative slurry formulations C in the above Tables when the same is stored, appears to lose capsule integrity not only in the premix formulation but also when added to detergent powder, as the sugar-silica wt.% ratio does not obey 65/35 to 95/5 ratio range that is importantly required for the capsule stability.

The Premix systems which were prepared viz., Systems A, B and C as described in the Table 1-3 above were all free flowing in nature, yet, had a total moisture content of 8-14%. What was found to be an important factor was the ‘free flow’ property of the premix, which allowed for homogeneous mixing and distribution within detergent powder.

Below 10% of moisture content, stability of MC capsules lowers and the capsules tends to become brittle and if the moisture content exceeds 20%, free flowable powder property gets completely destroyed together with loss of stability even if the select ingredients of the formulations are taken in consideration. Therefore, specified range of moisture content is important in the present invention.

Table 4: Technology A evaluation
TECHNOLOGY A - EVALUATION
STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - FRESH & CLEAN - RT FRAGRANCE - FRESH & CLEAN - 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 1.10 1.50 0.70 1.00
Neat Oil 0.50 0.80 0.50 0.50
Neat Slurry + G20 1.20 1.58 0.60 1.25
Neat Oil + G20 1.08 1.33 0.60 0.88
Technology A 2.13 3.25 0.50 2.50
System - Technology 1.08 2.50 0.80 1.50
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10


STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - CLEAN DELIGHT - RT FRAGRANCE - CLEAN DELIGHT 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 0.65 1.30 0.50 0.75
Neat Oil 0.80 1.00 0.00 0.30
Neat Slurry + G20 1.00 1.58 0.87 1.19
Neat Oil + G20 1.10 1.50 0.57 1.06
Technology A 0.88 3.25 0.50 2.10
System - Technology 1.00 1.50 0.60 1.25
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10

Table 5: Technology B evaluation

TECHNOLOGY B - EVALUATION
STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - FRESH & CLEAN - RT FRAGRANCE - FRESH & CLEAN - 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 1.10 1.50 0.70 1.00
Neat Oil 0.50 0.80 0.50 0.50
Neat Slurry + W250 1.50 2.38 0.00 1.00
Neat Oil + W250 1.00 1.50 0.00 0.50
Technology B 1.67 4.00 0.50 3.25
System - Technology 1.08 2.50 0.80 1.50
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10

STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - CLEAN DELIGHT - RT FRAGRANCE - CLEAN DELIGHT 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 0.65 1.30 0.50 0.75
Neat Oil 0.80 1.00 0.00 0.30
Neat Slurry + W250 1.11 2.33 0.79 1.38
Neat Oil + W250 0.90 1.00 0.40 0.90
Technology B 0.80 2.80 0.60 2.00
System - Technology 1.00 1.50 0.60 1.25
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10

Table 6: Technology C evaluation

TECHNOLOGY C - EVALUATION
STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - FRESH & CLEAN - RT FRAGRANCE - FRESH & CLEAN - 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 1.10 1.50 0.70 1.00
Neat Oil 0.50 0.80 0.50 0.50
Neat Slurry + NDA 1.00 1.53 0.85 1.60
Neat Oil + NDA (Not Compatible) 0.00 0.00 0.00 0.00
Technology C 2.71 4.10 1.10 3.20
System - Technology 1.08 2.50 0.80 1.50
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark (Surf Excel QW TL) 1.75 2.50 0.70 1.10


STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - CLEAN DELIGHT - RT FRAGRANCE - CLEAN DELIGHT 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Neat Slurry 0.65 1.30 0.50 0.75
Neat Oil 0.80 1.00 0.00 0.30
Neat Slurry + NDA 0.80 1.42 0.80 1.65
Neat Oil + NDA ( Not Compatible) 0.00 0.00 0.00 0.00
Technology C 2.25 3.13 0.50 2.75
System - Technology 1.00 1.50 0.80 1.80
Unperfumed Sample 0.30 0.50 0.00 0.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10


STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - FRESH & CLEAN - RT FRAGRANCE - FRESH & CLEAN - 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Technology A 2.13 3.25 0.50 2.50
Technology B 1.67 4.00 0.50 3.25
Technology C 2.71 4.10 1.10 3.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10

STUDY AT - RT / 500C- 4 WEEKS FRAGRANCE - CLEAN DELIGHT - RT FRAGRANCE - CLEAN DELIGHT 50C
CANDIDATES Pre - Rub Post - Rub Pre - Rub Post - Rub
Strength Strength Strength Strength
Technology A 0.88 3.25 0.50 2.40
Technology B 0.80 2.80 0.60 2.30
Technology C 2.25 3.23 0.50 2.50
Bench Mark ( Surf Excel QW TL) 1.75 2.50 0.70 1.10

Terminologies used as below for the above Tables
G 20 PPG-20 Methyl Glucose Ether
W250 Bis-PEG-18 Methyl Ether Dimethyl Silane
NDA acrylamido-N-propyltrimethylammonium chloride/acrylamide
Neat Slurry Aminoplast Encap Slurry
Neat Oil Neat Fragrance - Fresh & Clean and Clean Delight
Technology A, B,C Complete System A, B, C (According to Formulation)
System - Technology Complete System - (Minus) G 20/W250 /NDA
Unperfumed Sample Unperfumed powder
Bench Mark (Surf Excel QW TL) Bench Mark

Conclusion: In the above Tables and the related Figures 1a-d it is clearly seen that for the various types of fragrances and even at 50 ?C the strength profiles of the capsules of the premix in the detergent powder are adequately maintained.
The strength profiles for the above formulations A-C based technologies are also provided under Figures 1a-d studied for a time duration of at least 1 month.

It is to be noted that our defined process of forming flowable dry MF premix powders actually is specific in terms of the weight ratios which are employed, as well as, the manner in which this needs to be added to the detergent powder. In all the above three formulations provided by way of this present invention wherein flowable premix MF powders could be prepared with each system employing a different combination of ingredients to achieve the powdery material. In addition these systems also lend themselves to form dry premix powders of different particle sizes. Also, importantly these powders have moisture levels within 8-25% range and more specifically from 10-20% range, and, still more preferably between 11-18% range. Additional studies below on these powders have proven capsule stability and integrity on long term storage.
When the moisture content is varies the capsule stability in the premix is destroyed without providing for any suitable profile.
Table 7: Preferred formulation E2 including Control formulation E0 & E1& comparative formulation E3
Formulation 1/E0
( Base ) Formulation 2/ E1 Formulation 3/ E2 Formulation 4/ E3
Sr. No. Raw Material Name Vendor name %
1 SLES 2EO (28%) surfactant Galaxy 45 45 45 45
2 CDEA, non-ionic surfactant Galaxy 2 2 2 2
3 CAPB, amphoteric surfacatnt Galaxy 1.5 1.5 1.5 1.5
4 DS EDTA, chelating agent SD fine 0.1 0.1 0.1 0.1
5 Microcap Blue carees Keva 0.5 0.5 0.5
6 Acrylates polymer (Carbopol Aqua 30) Lubrizol 3
7 Urea Based polymer ( BYK 420) BYK Additive 0.8
8 NaOH 20% SD Fine 0.5 0.5 0.5 0.5
9 Water In-house 5 5 5 5
10 Kathon CG Dow 0.1 0.1 0.1 0.1
11 salt TATA 0.3 0.3 0.3 0.3
12 Water In-house Q.S Q.S Q.S Q.S
Total Qty 100 100 100 100

The above table reveals the relevance of cationic polymer together with other additives such as EDTA in a surfactant medium as a suspending aid for the capsules in accordance with the present invention to provide for not only a stable dispersion of hard shell capsules in said liquid detergent formulations but also enhanced fragrance performance/ strength and profile on fabrics post dry.

Table 8: Stability Tests Storage Conditions/ Assessment 5 Point rating scales (Odour Quality/ Change in colour)

Stability Tests Storage Conditions / Assessment in 5 Point rating scales (Odour Quality/ Change in colour)
SCORE STRENGTH / PROFILE COLOUR
0 Unchanged Unchanged
1 V. Slightly weakened V. Slightly changed
2 Slightly weakened Slightly changed
3 Markedly weakened Markedly changed
4 Strongly weakened Strongly changed
5 No perfume Completely Changed

Table 9: Observations
STORAGE CONDITIONS 5°C Refrigerator 25°C / Ambient humidity (RT) 50°C / 40 %RH OBSERVATIONS
4th Week LT RT HD
Labels Fragrance Dosage % Strength Note Strength Note Strength Note LT RT 50oC
E0 UnperfumedReg LD base 0.00 0 0 0 0 0 0 0 0 0 No changes
E1 Reg LD base with microcap 0.5 0 0 0 0 0 0 0 0 0 Microcap settle down at bottom of bottle in all temp.
E2 Reg LD base with acrylate polymer 0 0 0 0 0 0 0 0 0 0 No changes
E3 Reg LD base with acrylate polymer + Microcap blue carees 0.50 0 0 0 0 0 0 0 0 1 very slight color changed @ 50 deg

Remarks: Slurry settles down at bottom of the bottle in Reg LD base with microcap, hence sample failed flash stability; Reg LD base with acrylate polymer + Microcap blue carees performed well in fragrance & sample is found homogenous in appearance during stability hence sample passed the stability also as compared to Formulation E3 involving urea polymer, which involves an ingredient not in accordance with the present invention.

Table 10: MP Blue caries and benchmark
Profile
SOAK DAMP POP DRY (Pre - Rub) DRY (Post - Rub)
Surf Excel Front Load 3.16 2.84 3.38 1.53 1.72
Surf Excel Top Load 2.92 2.81 3.17 1.53 1.59
Blue cares 15% with cationic polymer, EDTA 2.91 2.34 3.06 2.31 3.03
Blue Cares MC Reg 2.66 2.47 3 1.63 2.59
Blue Cares MC Density Match 2.72 2.63 3.13 1.75 2.34

Strength
SOAK DAMP POP DRY (Pre - Rub) DRY (Post - Rub)
Surf Excel Front Load 3.31 2.69 3.44 1.31 1.53
Surf Excel Top Load 3.05 3 3.34 1.5 1.47
Blue cares 15% with cationic polymer, EDTA 2.84 1.95 3.44 2.13 3.05
Blue Cares MC Reg 2.63 2.23 3.22 1.5 2.55
Blue Cares MC Density Match 2.69 2.44 3.08 1.59 2.38

Remarks: Figs 2a-b shows the profile and the strength of the formulation in accordance with the present invention vis-à-vis the comparatives conventionally known and control formulations.

Object: To perform panel fragrance evaluation for 4 weeks stability samples of "Reg LD with encapsulates" samples kept at different temperature LT (5 deg), RT & HD (45 deg).
STABILITY EVALUATION DATA OF FORMULATION 3
Candidates:
AL 20 4 th week -Int. LD with Encap sample kept @LT (5deg)
AR 20 4 th week -Int. LD with Encap sample kept @ RT
AH 20 4 th week -Int. LD with Encap sample kept @ HD(45 deg)

Table 11: Results
Profile
SOAK POP DRY (Pre - Rub) DRY (Post - Rub)
4 th week -Int. LD with Encap sample kept @LT (5deg) 2.39 2.22 1.83 2.78
4 th week -Int. LD with Encap sample kept @ RT 2.17 2.56 1.94 2.56
4 th week -Int. LD with Encap sample kept @ HD(45deg) 2.61 2.39 1.44 2

Strength
SOAK POP DRY (Pre - Rub) DRY (Post - Rub)
4 th week -Int. LD with Encap sample kept @LT (5deg) 2.06 2.61 1.83 2.61
4 th week -Int. LD with Encap sample kept @ RT 1.94 2.83 1.94 2.39
4 th week -Int. LD with Encap sample kept @ HD(45 deg) 2.44 2.611 1.33 1.89

Remarks: Sample kept at HD (45deg) at 4th week is showing inferiority on both profile & strength in parameter:- Dry pre-rub & post-rub as plotted under Figures 3a-b.

STABILITY EVALUATION DATA OF FORMULATION 4 ABOVE

Object: To perform panel fragrance evaluation for 4 weeks stability samples of "Reg LD with encap" samples kept at different temperature LT (5 deg), RT & HD (45deg).
Candidates:
AL 20 4 th week -Int. LD with Encap sample kept @LT (5deg)
AR 20 4 th week -Int. LD with Encap sample kept @ RT
AH 20 4 th week -Int. LD with Encap sample kept @ HD(45 deg)

Table 12:
Profile
SOAK POP DRY (Pre - Rub) DRY (Post - Rub)
4 th week -Int. LD with Encap sample kept @LT (5deg) 2.39 2.22 1.83 2.78
4 th week -Int. LD with Encap sample kept @ RT 2.17 2.56 1.94 2.56
4 th week -Int. LD with Encap sample kept @ HD(45deg) 2.61 2.39 1.44 2

Strength
SOAK POP DRY (Pre - Rub) DRY (Post - Rub)
4 th week -Int. LD with Encap sample kept @LT (5deg) 2.06 2.61 1.83 2.61
4 th week -Int. LD with Encap sample kept @ RT 1.94 2.83 1.94 2.39
4 th week -Int. LD with Encap sample kept @ HD(45 deg) 2.44 2.611 1.33 1.89

Remarks: Sample kept at HD (45deg) is showing inferiority on both profile & strength in parameter:- Dry pre-rub & post-rub as plotted under Figures 4a-b.

LIQUID DETERGENT: Cationic Polymer impact Data
Candidates
DR Reg.LD base with Microcap Carees blue @0.5%
CA Reg.LD base with Microcap Carees blue @0.2%
EN Reg.LD base with Microcap Carees blue @0.3%
VJ Reg.LD base with Microcap Carees blue15% Adduct @2.0%
CK Reg.LD base with Microcap Carees blue15% Adduct @1.0%
VI Reg.LD base with Microcap Carees blue15% Adduct @3.0%

Table 13
Profile:

S No SOAK DAMP POP DRY (Pre - Rub) DRY (Post - Rub)
1 Reg.LD base with Microcap Carees blue @0.5% 3.05 1.91 3.00 1.85 2.45
2 Reg.LD base with Microcap Carees blue @0.2% 2.64 1.91 2.71 1.30 1.90
3 Reg.LD base with Microcap Carees blue @0.3% 2.67 2.14 2.75 1.75 2.45
4 Reg.LD base with Microcap Carees blue15% Adduct @2.0% 2.33 2.45 2.63 2.55 3.30
5 Reg.LD base with Microcap Carees blue15% Adduct @1.0% 1.85 1.91 2.35 1.80 2.70
6 Reg.LD base with Microcap Carees blue15% Adduct @3.0% 2.35 2.82 2.81 2.35 3.25

S No Strength
SOAK DAMP POP DRY (Pre - Rub) DRY (Post - Rub)
1 Reg.LD base with Microcap Carees blue @0.5% 2.95 1.86 3.29 1.90 2.60
2 Reg.LD base with Microcap Carees blue @0.2% 2.77 1.95 2.96 1.3 1.80
3 Reg.LD base with Microcap Carees blue @0.3% 2.71 2.23 3.08 1.50 2.60
4 Reg.LD base with Microcap Carees blue15% Adduct @2.0% 2.33 2.36 2.92 2.75 3.40
5 Reg.LD base with Microcap Carees blue15% Adduct @1.0% 2.10 1.91 2.69 1.75 2.70
6 Reg.LD base with Microcap Carees blue15% Adduct @3.0% 2.48 2.91 3.21 2.35 3.30

Remarks: S. No. 1, 2 & 3 are regular Microcap – Performance study in Liquid Detergent while S. No. 4, 5 & 6 – are Microcap treated with Cationic Polymer (Adduct) in liquid detergent wherein it is found that cationic polymer adduct in liquid detergent formulation enhances the performance of fragrance post dry delivery.

Microcapsule dilution study
Table 14: Liquid Detergent Evaluation
Code Candidates
Z87 Reg. Liquid detergent base with polymer
M7N Reg. LD base with 0.5% Micro-cap
D5Q Reg. LD base with 1:9 diluted Micro-cap

Candidates DRY (Pre-Rub) DRY (Post-Rub) POP
Profile Strength Profile Strength Profile Strength
Reg. Liquid detergent base with polymer 0.69 0.75 0.75 0.75 0.94 1.19
Reg. LD base with 0.5% Micro-cap,
concentrated slurry 2.25 2.06 2.75 3.31 2.71 3.36
Reg. LD base with 1:9 diluted Micro-cap, diluted slurry, 10%. 2.06 1.75 2.81 2.88 2.71 3.07

Remarks:-The performance of the candidate Reg. LD base with 0.5% Micro-cap is found to be good with respect to remaining two as plotted in Figure 6 and the same profile remains until 10% w/w. Also indicates concentrated slurry performance better than diluted slurry.

It is also a significant finding of the present invention that addition of a fixative, a humectant or a strongly charged cationic conditioning polymer or a combination thereof to the aqueous pre mix MF slurry followed by the addition of sugar and hydrophilic precipitated silica in a ratio between the 65/35 to 95/5 band serves as an effective vehicle for delivery of these capsules tofabric even while being delivered through detergent powders. As mentioned above three such formulation mixes are provided by the present invention relating to flowable powdery material which could be added to detergent powder in appropriate amounts.

The MF capsule pre-mix formulation comprising fixative, a humectant or a strongly charged cationic conditioning polymer or a combination thereof to the aqueous pre mix MF slurry followed by the addition of sugar and hydrophilic precipitated silica in a ratio between the 65/35 to 95/5 band serves as an effective vehicle for delivery of these capsules to fabric even while being delivered through detergent powders. In the process of preparing MF capsule pre-mix formulation the silica: sugar combination when actually added in two distinct phases with about 85% of the amount added during first step and the remaining 15% added after proper mixing was observed to offer optimal and desired deposition.
If the desired range of ratio between sugar and hydrophilic precipitated silica is not maintained, the premix suffer from structural instability due to insufficient moisture content. Therefore, MF capsules suffer leaching of fragrances.

While silicone wax can be considered as a humectant other variants of humectants include Sorbitol, Glycerol, Propylene glycol and other glycols.

The cationic conditioning polymers includes Polyquats, cationic acrylates, cationic acrylamides.

Yet another aspect of the present invention is also thus the sequence and hierarchy of addition of ingredients, as well as, the weight ratios in which each of them are addedindividually are key to optimal deposition of said capsules onto the fabrics. Hence, the fragrance delivery is directly impacted by the weight ratios of silica, sugar, fixative and the silicone wax employed.The silica: sugar combination when actually added intwo distinct phases with about 85% of the amount added during first step and the remaining 15% added after proper mixing has beenascertained to offer optimal deposition.

Also, important is that the addition of fixative, humectant or the strongly chargedcationic polymer to the original premix slurry such that final moisture level is between 7-30% and morepreferably between 10-25% band and yet more preferably in the 12-20% band. At this moisture level thepremix slurry of said select ingredients appears as a dry flowable powder which is added to the detergent powder formulation. Storage studies were conducted with the premix powder alone, and, premix powder added to detergent powder wherein it was found that Premix alone, is stable for at least 4 weeks, which was subsequently incorporated in detergent powder, results showing in Fig. 1 (a)-(d), Figs. 2, 3 that is stable for at least 1 month wherein the vehicular systems involving a fixative, a humectant or a strongly charged cationic conditioning polymer or combinations thereof have shown the capability of the coating system to protect MF capsules in storage.

An optical micrograph of a detergent powder in the systems/ formulations of the present invention containing the dried premix MF capsules after a month’s storage at 50?C proves that these capsules remain intact by and large upon storage (Figure 7) as compared to comparative system, not in accordance with the present invention. Further the efficacy of premix formulation in delivering MF capsules, and, consequently the delivery of fragrance has also been proven by internal panel studies in controlled studies vis-à-vis the fabric washed with normal commercially available detergent powder (as an internal control) that does not deliver any fragrance post washing wherein the fragrance gets solubilized in micelles and get washed away.

However, the MF slurry formulations of the present invention involving fixative, a humectant or a strongly charged cationic conditioning polymer or combinations thereof together with a select moisture content ensures the effective delivery and deposition of MF capsules on fabric surfaces, which, later on release fragrance upon shear action.

According to another aspect of the present invention a formulation is provided involving a synergistic combination of said silica, sugar, humectant/ positively charged cationic polymer including other additives such as fixatives mutually integrating thereby providing for a co-operative interaction and enhancing the benefits offered of effective delivery and lodging of MF capsules on fabric surfaces, whilst, being most optimal on both performance and costs.

The incorporation of MF slurries to surfactant based formulations such as liquid detergents also demonstrates the capability to deposit MF capsules in a rinse off situation. It was surprisingly found that an acrylate copolymer when used preferably within a 0.5% to 10% w/w and more preferably within a 1% to 5% weight ratio of liquid detergent was effective in suspending MF capsules in the liquid detergent and subsequent delivery (Table 14 Figure 6)The acrylate polymer serves as a good suspension aid thereby ensuring that MF capsules are well dispersed in the liquid, and, do not settle down with time. Long term storage stabilities of these systems have been established and evidence for deposition of MF capsules after liquid wash followed by drying cycle ascertained by objective panel olfactory measurements. Synergy derived by the addition of humectant or strongly charged cationic polymer with the acrylic copolymer suspending was found to aid enhanced performance and cost optimization. Stable capsular MF dispersions within liquid detergents and their stabilities have now been proven, in addition, to their efficacy in having fragrance containing capsules deposited after the liquid wash. It must be noted that the addition of only aqueous MF slurry to a clear laundry liquid formulation is capable of delivering the deposition of MF capsules post wash. However, the performance suffers because of sedimentation of MF capsules to the bottom of container necessitating thorough agitation of bottle prior to use, which the present invention could overcome.
Below 1% of polymer, the MC pre-mix settles down. Above 10% cost of the formulation as well as viscosity of the formulation will increase. Other ingredients such as Xanthum gum, Carrageenan, Guar gum, urea polymers, HPMC, CMC etc. were evaluated in the liquid detergent formulation for obtaining homogeneous pre-mix dispersion. But stable and homogeneous dispersion was not obtained.

Further to the abovesaid although, dispersing MF capsules using acrylate polymers are reported in prior art, transfer-efficiency of MF capsules of pre-mix in Liquid Detergent formulations is not known together with its stability which could be selectively achieved by the present invention based on the select ingredients employed in the slurry.

Hence achieving stable dispersions of MF capsules in a liquid detergent base employing an acrylate copolymer therefore precludes the consumer need and the effort which is required to shake the formulation before use. It has been established by way of the present invention that addition of acrylate polymer in amounts 0.5% to 10% w/w and more preferably within a 1% to 5% weight ratio of liquid detergent results in a uniform stable capsular dispersion that is efficient in depositing the capsules post wash and is also storage stable.

It is thus possible following the disclosed present advancement in knowledge to provide for systems/formulations involving modified aqueous slurries of hard shell capsules of the type MF (Melamine-formaldehyde containing fragrance capsules) type, and, a hierarchical process for the preparation of such MF premixes. Such MF premixes present in powdery flowable form have been shown to maintain the integrity of the MF capsules over a period of time without any compromise in its efficacy. Such systems or mixes ensure high deposition efficiencies of transfer of fragrance containing capsules. In addition it is also demonstrated that employing a suitable acrylate copolymer as a suspension aid enhances the stabilities of the MF capsules in liquid detergent and prevents sedimentation under gravity. It was also found by way of the present invention that employing a net positive charge on the MF slurry by the addition of strongly charged cationic polymers ensures that MF capsule delivery efficiencies onto cotton fabrics are significantly enhanced post washing, that is also stable on shelf based on the select ingredient employed.
,CLAIMS:We Claim:

1. Slurry formulation of fragrance capsules comprising a synergistic combination of
i. hard shell capsules comprising MF(melamine-formaldehyde) capsules;
ii. silica;
iii. sugar; with moisture content in the range of 8-25% adapted as an improved vehicle for capsule integrity during storage and transportation.

2. Slurry formulation as claimed in claim 1 comprising humectants and/or cationic polymer adapted for aqueous slurry favouring premix powder with moisture content in said 8-25% range suitable for powder detergent formulations.

3. Slurry formulation of fragrance capsules as claimed in anyone of claims 1 or 2 comprising
i. MF (melamine-formaldehyde) capsules in the range of 5-50 wt.%;
ii. silica 0.05-85 wt.% preferably hydrophilic precipitated silica;
iii. sugar 7-95 wt.% preferably sucrose; and such that the ratio of sugar and silica is in ratio between the 65/35 to 95/5;
iv. humectant 0.05-60 wt.%;
said moisture content being in the range of 10-14%.

4. Slurry formulation of fragrance capsules as claimed in anyone of claims 1-3 comprising
i. MF (melamine-formaldehyde) capsules in the range of 5-50 wt.%;
ii. silica 0.05-85 wt.% preferably hydrophilic precipitated silica;
iii. sugar 7-95 wt.% preferably sucrose; and such that the ratio of sugar and silica is in ratio between the 65/35 to 95/5;
iv. cationic polymer 0.5-25 wt.%;
said moisture content being in the range of 10-14%.

5. Slurry formulation as claimed in any preceding claims wherein said humectant includes silicone wax, sorbitol, Glycerol, glycols including Propylene glycol, PPG-20 Methyl Glucose Ether, Bis-PEG-18 Methyl Ether Dimethyl Silane.

6. Slurry formulation as claimed in any preceding claims wherein said cationic polymer includes Polyquats, cationic acrylates, cationic acrylamides.

7. Slurry formulation as claimed in any preceding claims comprising hard shell capsules including MF (melamine-formaldehyde) capsules, Aminoplast encapsulates, Urea- Formaldehyde Capsules.

8. Slurry formulation as claimed in any preceding claims comprising fixatives including glycerol, silicones, esters, acrylates; and additives including sodium chloride, sodium Carbonate, calcium carbonate, calcium magnesium carbonate, hydrated magnesium silicate.

9. Method of preparation of slurry formulation of fragrance capsules as claimed in claims 1-8 comprising simple blending of a synergistic combination of ingredients comprising
i. hard shell capsules comprising MF (melamine-formaldehyde) capsules;
ii. silica;
iii. sugar;
in hierarchical manner and controlling the moisture content in the range of 8-25% and obtaining therefrom said slurry formulation adapted as an improved vehicle for capsule integrity during storage and transportation.

10. Method of preparation of slurry formulation as claimed in claim 9 comprising blending said silica-sugar combination in two distinct phases with said hard shell capsules comprising adding about 85% of silica-sugar in the first step and remaining 15% post mixing in the first step with moisture controlled in the levels of 10-14 % favouring optimal post dry fragrance deposition.

11. Slurry formulation of fragrance capsules suitable for liquid detergents comprising positively charged cationic polymer 0.5-10wt.% preferably in the range of 1-5 wt.% as a synergistically co-acting suspension aid in a surfactant medium favouring not only stable dispersion of hard shell capsules in said liquid detergent formulations but also enhanced fragrance performance/ strength and profile on fabrics post dry.

Dated this the 12th of February 2019

Anjan Sen
Of Anjan Sen and Associates
(Applicants Agent)
(IN/PA-199)